&nbsp718 &nbspFXUS10 KWNH 031646 &nbspPMDHMD &nbsp &nbspMODEL DIAGNOSTIC DISCUSSION &nbspNWS WEATHER PREDICTION CENTER COLLEGE PARK MD &nbsp1144 AM EST SAT MAR 03 2018 &nbsp &nbspVALID MAR 03/1200 UTC THRU MAR 07/0000 UTC &nbsp &nbsp12Z MODEL EVALUATION...ALONG WITH MODEL PREFERENCES AND CONFIDENCE &nbsp~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ &nbsp&nbsp &nbsp..POWERFUL NOR'EASTER PULLING AWAY FROM THE EAST COAST &nbsp &nbsp~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ &nbsp &nbspPREFERENCE: GENERAL MODEL BLEND &nbspCONFIDENCE: ABOVE AVERAGE &nbsp &nbspTHE MODELS ARE IN VERY GOOD AGREEMENT IN TAKING THE STRONG &nbspNOR'EASTER AWAY FROM THE EAST COAST OVER THE NEXT 24 HOURS AND OUT &nbspOVER THE OPEN ATLANTIC OCEAN. A GENERAL MODEL BLEND WILL BE &nbspPREFERRED GIVEN THE MINIMAL MASS FIELD SPREAD. &nbsp &nbsp&nbsp &nbsp..DEEP CLOSED LOW IMPACTING THE WESTERN U.S. TODAY &nbsp&nbsp &nbsp..NEGATIVELY TILTED TROUGH APPROACHING THE PLAINS ON SUNDAY &nbsp &nbsp~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ &nbspPREFERENCE: GENERAL MODEL BLEND...THROUGH 60 HOURS &nbsp 06Z GEFS MEAN/00Z ECENS MEAN BLEND...AFTER 60 HOURS &nbspCONFIDENCE: ABOVE AVERAGE...BECOMING BELOW AVERAGE AFTER 60 HOURS &nbsp &nbspA DEEP LAYER CLOSED LOW AND ASSOCIATED BROAD TROUGH IMPACTING THE &nbspWEST COAST WILL GRADUALLY BE CROSSING THE INTERMOUNTAIN REGION &nbspTHROUGH SUNDAY. THE MODELS THEN INDICATE ENERGY LIFTING OUT OF THE &nbspBASE OF THE TROUGH BY SUNDAY NIGHT WHICH WILL ALLOW THE TROUGH TO &nbspTAKE ON A NEGATIVE TILT OUT ACROSS THE CENTRAL/NORTHERN PLAINS ON &nbspMONDAY. EXPECT A NEW MID/UPPER LEVEL LOW CENTER TO EVOLVE AS WELL &nbspAS THE SYSTEM AMPLIFIES. SURFACE LOW PRESSURE OVER THE GREAT BASIN &nbspTHROUGH SUNDAY IS EXPECTED TO REORGANIZE OVER THE PLAINS ON MONDAY &nbspAND BEGIN LIFTING ACROSS THE UPPER MIDWEST BY MONDAY NIGHT. THE &nbspGUIDANCE IS GENERALLY IN GOOD AGREEMENT WITH THEIR TIMING AND &nbspDEPTH OF THE TROUGH EVOLUTION THROUGH MONDAY, AND THE SPREAD WITH &nbspTHE SURFACE LOW DETAILS ACROSS THE PLAINS IS RATHER MINIMAL. &nbsp &nbspMORE SPREAD THOUGH OCCURS MONDAY AND TUESDAY AS THIS SYSTEM &nbspENCOUNTERS A VERY BLOCKY DOWNSTREAM PATTERN OVER EASTERN NORTH &nbspAMERICA. MOST OF THE MODELS REFOCUS THEIR RESPECTIVE CLOSED LOW &nbspFEATURES MORE TO THE EAST OVER PARTS OF THE MIDDLE MISSISSIPPI &nbspVALLEY AND THE LOWER GREAT LAKES REGION BY THE END OF THE PERIOD &nbspAND ALSO SHOW SOME BINARY INTERACTION WITH A CLOSED LOW FARTHER &nbspNORTH OVER ONTARIO TO THE SOUTH OF HUDSON BAY. THE 00Z UKMET TENDS &nbspTO HAVE MORE ENERGY FARTHER NORTH OVER THE GREAT LAKES REGION AND &nbspTAKES ITS SURFACE LOW A LITTLE NORTH OF THE MODEL CONSENSUS. THE &nbsp12Z GFS IS A LITTLE MORE SUPPRESSED WITH ITS HEIGHT FALLS AND HAS &nbspMORE ENERGY IMPACTING THE OHIO VALLEY. THE 00Z ECMWF IS NORTH OF &nbspTHE GFS WITH ITS SURFACE LOW EVOLUTION ON TUESDAY AND MANY OF THE &nbspECENS MEMBERS ARE NORTH AS WELL IN SUPPORT OF THE ECMWF. THE GEFS &nbspMEMBERS TEND TO HAVE TWO CAMPS OF LOW PRESSURE BY LATE TUESDAY &nbspWITH ONE AREA OF LOW PRESSURE OVER OHIO AND ANOTHER ONE BACK OVER &nbspILLINOIS. HOWEVER, ALOFT, THE GEFS MEAN IS A BIT NORTHWEST OF THE &nbspDETERMINISTIC GFS. THE 00Z CMC AND MANY CANADIAN ENSEMBLE MEMBERS &nbspATTEMPT TO SPLIT THE DIFFERENCE LATITUDINALLY WITH THE LOW &nbspPRESSURE WAVE. CONFIDENCE BECOMES LIMITED BY TUESDAY, BUT THE &nbspPREFERENCE WILL BE FOR A GENERAL MODEL BLEND THROUGH MONDAY WITH &nbspTHIS SYSTEM, AND THEN A COMPROMISE BETWEEN THE 06Z GEFS MEAN AND &nbsp00Z ECENS MEAN THEREAFTER. THIS WOULD BEST APPROXIMATE THE MODEL &nbspCONSENSUS AS WELL. &nbsp &nbsp&nbsp &nbsp..TROUGH DIGGING SOUTHEAST ACROSS THE NORTHEAST ON MONDAY &nbsp &nbsp~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ &nbspPREFERENCE: BLEND OF THE 12Z GFS AND 00Z ECMWF &nbspCONFIDENCE: AVERAGE &nbsp &nbspTHE MODELS TAKE A PORTION OF THE TROUGH/CLOSED LOW JUST SOUTHWEST &nbspOF HUDSON BAY AND SLOWLY SHIFT IT SOUTHEAST ACROSS QUEBEC ON &nbspSUNDAY AND THEN IN MORE OF SHEARED FASHION DOWN ACROSS THE &nbspNORTHEAST ON MONDAY AS THE SYSTEM ENCOUNTERS A BLOCKING HIGH THAT &nbspIS SETTLING SOUTHWEST FROM SOUTHERN GREENLAND. THE GUIDANCE &nbspCOMPARED TO YESTERDAY HAS TRENDED TOWARD MORE ENERGY DROPPING &nbspSOUTHEAST ACROSS THE NORTHEAST WITH A BETTER DEFINED CLOSED LOW &nbspFEATURE. THIS ENERGY THEN QUICKLY GOES SOUTHEAST AND OFFSHORE BY &nbspMONDAY. THE 12Z NAM AND 00Z CMC BECOME A LITTLE SLOWER THAN THE &nbsp12Z GFS AND 00Z ECMWF, BUT THE 00Z UKMET DOES FAVOR THE SLOWER &nbspCAMP. THE LATEST GEFS MEAN AND ECENS MEAN FAVOR THE FASTER &nbspSOLUTIONS. WILL LEAN TOWARD THE MORE PROGRESSIVE GFS AND ECMWF &nbspSOLUTIONS FOR NOW. &nbsp &nbsp&nbsp &nbsp..SHORTWAVE TROUGH OVER THE NORTHERN HIGH PLAINS TUESDAY &nbsp &nbsp~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ &nbspPREFERENCE: GENERAL MODEL BLEND &nbspCONFIDENCE: SLIGHTLY ABOVE AVERAGE &nbsp &nbspTHE GUIDANCE DROPS ANOTHER SHORTWAVE TROUGH DOWN ACROSS THE &nbspNORTHERN HIGH PLAINS BY TUESDAY. THERE IS SOME MINOR DEPTH &nbspDIFFERENCES BY LATE TUESDAY OVER MONTANA WITH THE HEIGHT FALLS, &nbspBUT WILL SUGGEST A GENERAL MODEL BLEND FOR THE TIME BEING. &nbsp &nbspPREVIOUS MODEL TRENDS AT WWW.WPC.NCEP.NOAA.GOV/HTML/MODEL2.SHTML &nbspPREVIOUS 500 MB FORECASTS AT &nbspWWW.WPC.NCEP.NOAA.GOV/H5PREF/H5PREF.SHTML &nbsp &nbspORRISON &nbsp &nbsp &nbsp